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US2567791A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of heat-treating gray cast iron

Assignee: Huntington Alloys Corp
•
Filing: 1949-08-10
•
Granted: 1951-09-11
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Expires: 1969-08-10
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Abstract

No abstract record available.

Inventors

  • 👤 Frederick G Sefing

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 06:37
CPC Classifications
C; C21; C21D; C21D6/00; C21D6/04; C21D5/00; C22; C22C; C22C37/00; C22C37/10

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 135 words
THE IMPROVED PROCESS FOR PRODUCING A HARD, WEAR-RESISTANT, CORROSION-RESISTANT ALLOY GRAY CAST IRON CASTING WHICH COMPRISES SUBJECTING AN ALLOY GRAY CAST IRON CASTING CONTAINING ABOUT 2.5% TO ABOUT 3% CARBON, ABOUT 7.5% TO ABOUT 9% NICKEL ABOUT 3.5% TO ABOUT 4% COPPER, ABOUT 2% TO ABOUT 2.5% CHROMIUM, ABOUT 1.75% TO 2.25% SILICON, AND THE BALANCE ESSENTIALLY IRON TO A THERMAL TREATMENT COMPRISING HEATING SAID CASTING TO A TEMPERATURE OF ABOUT 1600* F. TO ABOUT 1800* F., RAPIDLY COOLING SAID HEATED CASTING TO A TEMPERATURE BELOW ABOUT 900* F. TO SOFTEN SAID CASTING TO A MACHINABLE HARDNESS LEVEL OF ABOUT 180 TO ABOUT 250 BRINELL, AND THEREAFTER SUBJECTING SAID CASTING TO A HARDENING TREATMENT AT A TEMPERATURE BELOW ABOUT MINUS 70* F. TO HARDEN SAID CASTING TO A HARDNESS OF AT LEAST ABOUT 450 BRINELL.
Claim 2
Dependent Claim 135 words
THE IMPROVED PROCESS FOR PRODUCING A HARD, WEAR-RESISTANT, CORROSION-RESISTANT ALLOY GRAY CAST IRON CASTING WHICH COMPRISES SUBJECTING AN ALLOY GRAY CAST IRON CASTING CONTAINING ABOUT 2.5% TO ABOUT 3% CARBON, ABOUT 7.5% TO ABOUT 9% NICKEL ABOUT 3.5% TO ABOUT 4% COPPER, ABOUT 2% TO ABOUT 2.5% CHROMIUM, ABOUT 1.75% TO 2.25% SILICON, AND THE BALANCE ESSENTIALLY IRON TO A THERMAL TREATMENT COMPRISING HEATING SAID CASTING TO A TEMPERATURE OF ABOUT 1600* F. TO ABOUT 1800* F., RAPIDLY COOLING SAID HEATED CASTING TO A TEMPERATURE BELOW ABOUT 900* F. TO SOFTEN SAID CASTING TO A MACHINABLE HARDNESS LEVEL OF ABOUT 180 TO ABOUT 250 BRINELL, AND THEREAFTER SUBJECTING SAID CASTING TO A HARDENING TREATMENT AT A TEMPERATURE BELOW ABOUT MINUS 70* F. TO HARDEN SAID CASTING TO A HARDNESS OF AT LEAST ABOUT 450 BRINELL.

References Cited (Backward Citations)

US2530545A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-09-10 1955-03-12 1955-09-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-09-10 1959-03-12 1959-09-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-09-10 1963-03-12 1963-09-11 $7700.00 Window Closed / Lapsed

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